Method and apparatus for cementing while running casing in a well bore

Abstract

An improved method and apparatus for dropping a ball, plug or dart during oil and gas well operations (e.g., cementing operations) employs a specially configured valving member with curved and flat portions that alternatively direct fluid flow through a bore or opening in the valving member via an inner channel or around the periphery of the valving member in an outer channel. In one embodiment, the ball(s), dart(s) or plug(s) are contained in a sliding sleeve that shifts position responsive to valve rotation. An optional indicator indicates to a user or operator that a ball or plug has passed a selected one of the valving members.

The invention claimed is: 
     
       1. A ball and plug dropping head for use in sequentially dropping one or more balls and plugs into a well casing string, comprising:
 a) a module having an upper end with an inlet adapted to be fluidly connected in line with the lower end of a top drive; 
 b) the well casing string; 
 c) the module having a lower end with an outlet that is generally aligned with the inlet and that is connected to the well casing string; 
 d) the module having a main flow channel that connects the inlet and the outlet; 
 e) the module having a plurality of sections spaced between the inlet and the outlet, at least some of the sections being valves with valving members, each valving member having a flow bore, and being movable between open flow and closed flow positions, the module including sections that are not valves; 
 f) the module having one or more fluid flow channels with a curvature, wherein said one or more fluid flow channels enable fluid to bypass the valving members when one of the valving members is in the closed flow position each fluid flow channel valving member having a curved surface that has the same curvature as the curvature of the fluid flow channel; 
 g) at least one of the valving members having a cross section that, in the closed flow position, does not valve fluid flow in the main flow channel; 
 h) wherein fluid flow in the main channel flows around the valving member when the valving member is in the closed flow position and through the valving member when the valving member is in the open flow position; 
 I) wherein in the open flow position each valving member bore enables a ball or plug to pass therethrough; 
 j) wherein in the open flow position each valving member flow bore enables circulating fluid to pass downwardly through said flow bore when neither the ball nor plug is in the valving member flow bore; and 
 k) wherein the valves and sections that are not valves are connected with threaded connections. 
 
     
     
       2. The ball and plug dropping head of  claim 1 , wherein at least one valve has a pair of opposed, generally flat surfaces. 
     
     
       3. The ball and plug dropping head of  claim 1 , wherein at least one valving member has a valve flow bore that enables passage of a plug of a diameter of 6.5 inches. 
     
     
       4. The ball and plug dropping head of  claim 1 , wherein at least one valving member in the closed position has a generally cylindrically shaped cross section. 
     
     
       5. The ball and plug dropping head of  claim 1 , wherein at least one valving member in the closed position has a generally rectangular shaped cross section. 
     
     
       6. The ball and plug dropping head of  claim 1 , wherein the module has a working tension of two million pounds. 
     
     
       7. The ball and plug dropping head of  claim 1 , wherein the module has an internal working pressure of 15,000 psi. 
     
     
       8. The ball and plug dropping head of  claim 1 , wherein the module has a working torque of 50,000 foot pounds. 
     
     
       9. The ball and plug dropping head of  claim 8 , wherein the module has a working torque of 50,000 foot pounds in either of two rotational directions. 
     
     
       10. The ball and plug dropping head of  claim 1 , wherein there are multiple valving members that each enable fluid flow around the valving member when the valving member is closed. 
     
     
       11. The method of  claim 1 , further comprising enabling fluid to flow around the valving member when the valving member is closed. 
     
     
       12. A ball and plug dropping head for use in sequentially dropping one or more balls and plugs into a well casing string, comprising:
 a) a top drive having a lower end portion; 
 b) a tool body comprised of a plurality of sections, each section connected to another section with a threaded connection, the tool body having an inlet at its upper end adapted to be fluidly connected in line with the lower end of the top drive, the tool body having an outlet generally aligned with the inlet; 
 c) the well casing string attached to the tool body at the outlet; 
 d) the tool body having a main flow channel that connects the inlet and the outlet, the main flow channel having an inner channel and an outer channel; 
 e) the sections including a plurality of valves spaced between the inlet and the outlet, each valve having a flow bore, and a valving member that is movable between open flow and closed flow positions and one or more sections that are not valves; 
 f) the outer channel having a curvature and enabling fluid to bypass the valving member when the valving member is in the closed flow position, and the valving member having a curved surface that has the same curvature as the curvature of the outer channel; 
 g) at least one of the valving members having a cross section that, in the open flow position, does not valve fluid flow in the inner channel; 
 h) wherein fluid flow flows around the valving member via the outer channel when it is in the closed flow position and through the valving member and the inner channel when the valving member is in the open flow position; 
 I) wherein each valving member is configured to hold a ball or plug when closed; 
 j) wherein in the open flow position each valve flow bore enables a ball or plug to pass therethrough; 
 k) wherein in the open flow position, each valve flow bore enables circulating fluid to pass 
 
       downwardly therethrough when neither a ball nor plug is in the valve flow bore. 
     
     
       13. The ball and plug dropping head of  claim 12 , wherein at least one valving member has a pair of opposed, generally flat surfaces. 
     
     
       14. The ball and plug dropping head of  claim 12 , wherein at least one valving member has a valve opening that enables passage of a plug of a diameter of 6.5 inches. 
     
     
       15. The ball and plug dropping head of  claim 12 , wherein at least one valving member in the closed position has a generally cylindrically shaped cross section. 
     
     
       16. The ball and plug dropping head of  claim 12 , wherein at least one valving member in the closed position has a generally rectangular shaped cross section. 
     
     
       17. The ball and plug dropping head of  claim 12 , wherein the tool body has a working tension of two million pounds. 
     
     
       18. The ball and plug dropping head of  claim 12 , wherein the tool body has an internal working pressure of 15,000 psi. 
     
     
       19. The ball and plug dropping head of  claim 12 , wherein the tool body has a working torque of 50,000 foot pounds. 
     
     
       20. The ball and plug dropping head of  claim 19 , wherein the tool body has a working torque of 50,000 foot pounds in either of two rotational directions. 
     
     
       21. The ball and plug dropping head of  claim 12 , wherein there are multiple valving members that each enables fluid flow around the valving member when the valving member is closed. 
     
     
       22. A ball and plug dropping head for use in sequentially dropping one or more balls and plugs into a well casing string, comprising:
 a) a top drive having a lower end portion; 
 b) a multi-section tool body having upper and lower end positions, an inlet at its upper end portion adapted to be fluidly connected in line with the lower end portion of the top drive, the lower end portion providing an outlet generally aligned with the inlet; 
 c) the well casing string attached to the lower end portion of the tool body; 
 d) the tool body having a main flow channel that connects the inlet and the outlet; 
 e) the main channel divided into inner and outer channels, the outer channel having a curvature; 
 f) sections of the tool body including a plurality of valving members spaced between the inlet and the outlet, each valving member having a flow bore, and being movable between open and closed positions, the tool body including one or more sections that are non-valving members; 
 g) the outer channel enabling fluid to bypass the valving members when a valving member is in the closed position, the valving member having a curved surface that has the same curvature as the curvature of the outer channel; 
 h) at least one of the valving members having a curved surface that closes the inner but not the outer channel in the closed position and wherein in the open position the flow bore of the valving member generally aligns with the inner channel; 
 i) wherein fluid flow in the main channel flows around the valving member when it is in the closed position and through the valving member when it is in the open position; 
 j) wherein each valving member is configured to support a ball or plug when closed; 
 k) wherein in the open position each valve flow bore permits a ball or plug to pass therethrough; and 
 l) wherein in the open position each valve flow bore enables circulating fluid to pass 
 
       downwardly therethrough when neither a ball nor plug is in the valve flow bore. 
     
     
       23. A method of sequentially dropping one or more balls, darts or plugs into an oil and gas well casing string, comprising the steps of:
 a) providing a tool body having multiple sections, an inlet at its upper end adapted to be fluidly connected in line with the lower end of a top drive, an outlet generally aligned with the inlet, a main flow channel that connects the inlet and the outlet, the flow channel having a curvature, and wherein the sections of the tool body include a plurality of valving members spaced between the inlet and the outlet, each valving member having a flow bore, and being movable between open and closed positions, the tool body including one or more sections that are not valving members; 
 b) supporting the tool body with a top drive; 
 c) supporting the oil and as well casing string with the tool body; 
 d) enabling fluid to bypass the valving members when a valving member is in the closed position; 
 e) preventing fluid flow in the main flow channel when a valving member is in a closed position; 
 f) enabling fluid flow in the main channel around the valving member when the valving member is in the closed position and through the valving member when the valving member is in the open position the valving member having a curved surface that has the same curvature as the curvature of the outer channel; 
 g) supporting a ball or plug with a valving member when the valving member is closed; and 
 h) permitting a ball or plug to pass through the valving member when the valving member is in the open position. 
 
     
     
       24. The method of  claim 23 , wherein at least one valve has a pair of opposed, generally flat surfaces. 
     
     
       25. The method of  claim 23 , wherein at least one valving member has a valve opening that enables passage of a plug of a diameter of 6.5 inches. 
     
     
       26. The method of  claim 23 , wherein at least one valving member in the closed position has a generally cylindrically shaped cross section. 
     
     
       27. The method of  claim 23 , wherein at least one valving member in the closed position has a generally rectangular shaped cross section. 
     
     
       28. The method of  claim 23 , wherein the body has a working tension of two million pounds. 
     
     
       29. The method of  claim 23 , wherein the body has an internal working pressure of 15,000 psi. 
     
     
       30. The method  claim 23 , wherein the body has a working torque of 50,000 foot pounds. 
     
     
       31. The method  30 , wherein the body has a working torque of 50,000 foot pounds in either of two rotational directions. 
     
     
       32. A method of dropping one or more balls or plugs into a well casing string, comprising:
 a) providing a multi-section tool body having an inlet at its upper end, an outlet generally aligned with the inlet, a flow channel that connects the inlet and the outlet, a plurality of sleeves that divide the flow channel into an inner channel and an outer channel, the outer channel having a curvature, a plurality of valving members spaced between the inlet and the outlet, each valving member having a flow bore and being movable between open and closed positions, and each valving member having a curved surface that has the same curvature as the curvature of the outer channel the tool body having sections that are not valving members; 
 b) supporting the tool body with a top drive, the tool body being fluidly connected in line with a lower end of the top drive; 
 c) supporting the well casing string with the tool body; 
 d) enabling fluid to bypass the valving members via the outer channel when one of the valving members is in the closed position; 
 e) flowing fluid in the outer channel and around the valving member when the valving member is in the closed position and through the valving member via the inner channel when the valving member is in the open position; 
 f) supporting a ball or plug with the valving member when closed; 
 g) permitting a ball or plug to pass the valving member when open; and 
 h) wherein one of the tool body sections is connected to a section of the casing.